This invention relates to flyer bows. Flyer bows for use on twisting machines are well known in the art. Twisting machines with flyer bows can be used to make twisted cables for a wide variety of uses. Flyer bows, including those related to this invention, can be used with pairing, tripling, quadding, bunching and twisted machines for wires. A typical flyer bow is generally rectangular in cross section. Wires to be twisted pass longitudinally along the inside surface of the flyer bow and are guided along the surface through ceramic or metal wire guides. A groove or recess in the inside surface of the flyer bow is often incorporated into the design of the flyer bow in order to nest the wires to be twisted close to the surface of the flyer bow. This configuration minimizes drag on the wires due to wind that sweeps transversely across the flyer bow during use. Flyer bows with airfoil shapes have been successfully used to increase speed of the winding machines with the benefits of minimum power draw and reduced operational noise. However, the airfoil does little, if anything, to minimize the effect of drag on the exposed wires. Furthermore, the exposed wire guides create additional drag on the flyer bow as it rotates.
A typical construction and operation of a twisting machine and flyer bow is disclosed and described in U.S. Pat. No. 3,945,182, the entire contents of which are incorporated herein by reference. As described in U.S. Pat. No. 3,945,182, a typical flyer bow is arcuate along its length and transversely flat. That is, it is generally rectangular, or at least has opposed flat parallel faces, and it is arcuate along its length. U.S. Pat. No. 3,945,182 discloses the feature of incorporating a groove or recess in the inside surface of the flyer bow and a corresponding ridge or protrusion on the outer surface of the flyer bow. The wires to be twisted nest within the groove to protect the wires from windage that sweeps transversely across the flyer bow as it rotates along its orbital path around a longitudinal axis.
Typical prior art flyer bows have wire guides mounted on the inner surface. These wire guides are typically semicircular in shape and present a flat and blunt exposed air surface. The prior art wire guides are typically secured to the flyer bow by nuts which extend above the top surface of the flyer bow and are exposed to air as the flyer bow rotates. All of this creates drag of the flyer bow as it rotates.
U.S. Pat. No. 5,509,260 discloses a guiding bow for an elongated element in a twisting or winding apparatus. At least part of the length of the guiding bow has a transversal cross section which is streamlined. The core of the guiding bow may be made of a load carrying material, the sheath of a synthetic material.
U.S. Pat. No. 5,809,763 discloses a flyer bow having inner and outer surfaces, and at least one surface is curved to form an airfoil in cross section.
U.S. Pat. No. 4,072,003 discloses a double twisting machine of a flyer type, which comprises a pair of rotatable fliers, a pair of bow guides formed with a through bore for allowing wire elements to pass therethrough, two pairs of guide holders each retained in one of each of the fliers for holding one end of each of the bow guides and two pairs of shock-absorbing elastic members each interposed between each of the fliers and each of the bow guides through the corresponding one of the guide holders. The fliers are in spherical contact with the guide holders so as to assure smooth swinging motions of the bow guides.